Percentages + time - math problems

Number of problems found: 70

  • In the
    covid19 In the workshop, it was necessary to quickly complete the production of veils for the hospital. The workshop staff promised to work an additional 240 hours to produce this order in March. The workshop has 8 employees who work 160 hours a month. What perce
  • Birthday paradox
    holland How large must the group of people be so that the probability that two people have a birthday on the same day of the year is greater than 90%?
  • Slow saving in banks
    penize_5 How long will it take to save € 9,000 by depositing € 200 at the beginning of each year at 2% interest?
  • What is
    exp_growth2 What is the annual percentage increase in the city when the population has tripled in 20 years?
  • Ditch
    vykop The excavator dug 40% of the excavation in 2 hours 20 minutes. How long does it take him to dig the whole ditch?
  • Savings
    bankovka The depositor regularly wants to invest the same amount of money in the financial institution at the beginning of the year and wants to save 10,000 euros at the end of the tenth year. What amount should he deposit if the annual interest rate for the annua
  • Christmas holidays
    christmas How many percent take Christmas holidays lasting 18 days from a school year that lasts 303 days? Round the result to two decimal places
  • Corona virus
    covid19 Calculate an estimate of the percentage of GDP (Gross Domestic Product) declined due to the quarantine related to the corona COVID-19 virus that lasts for 2 months, during which time the economic activity is down by 80%.
  • Volume of wood
    wood Every year, at the same time, an increase in the volume of wood in the forest is measured. The increase is regularly p% compared to the previous year. If in 10 years the volume of wood has increased by 10%, what is the number p?
  • Growth of wood
    wood The annual growth of wood in the forest is estimated at 2%. In how many years will make the forest volume double?
  • Mary
    koralky2 Mary is 12 years old, which is 40% of the age of her mother. How many percent of her mother's age will Mary have after the next 12 years?
  • Two companies
    calendar The family ordered two companies to modify the garden. The first would be done in 20 days, the second would take 40% less time. How long will they work together if the second company started working when the first worked for 4 days?
  • Harvest time
    clocks2 Grandma and granddaughter Julka reap currants in 15 hours of working together. Julka herself would have currants 10 days after 6 hours of work a day. Find by what percentage the grandma's harvest time was shortened when the granddaughter was involved in c
  • Break time
    skola_1 Calculate how many percent of school time is spent on breaks. Calculate data for the whole week.
  • Car down
    car_1 Sarah buys a car costing $12,500. It depreciates in value by 8% in the first year, 10% the second year and 5% in the third year. Calculate the value of a car after the third year.
  • An investment
    exp_growth2 How long will it take for an investment to double at a simple interest rate of 5.10% p. A. ? Express the answer in years and months, rounded up to the next month.
  • Curiosity factor
    wwww A blogger starts a new website, initially the number of the traffic is 293 due to their curiosity factor. The business owner estimated that the traffic will increase by 2,6% per week. What will be the number of it in week 5?.
  • Helmet
    Clock0400_7 Nowadays cycling better results could be obtained not only due to rider physical preparation but also thanks to using updated technologies. One of the essential parts of the rider´s equipment is his or her helmet. While most bikers wear a helmet mainly to
  • A man 2
    penize_49 A man divides $10,000 into two investments, one at 10% and the other at 30%. Find how much is invested at each rate so that the two investments produce the same income annually.
  • The crime
    crime The crime rate of a certain city is increasing by exactly 7% each year. If there were 600 crimes in the year 1990 and the crime rate remains constant each year, determine the approximate number of crimes in the year 2025.

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